Improvement in wood-bending machines



Woocl B ending' Machine 117663 mmm 1187i Fig: l

` shaping the same.

UNITED STATES FFICE.

LEVI E. MINOTT, OF SHEBOYGAN, WISCONSIN.

Specification forming part of Letters Patent No. 117,663, dated August1, 1871.

To all 'whomit may concern:

Be it known that I, LEVI E. MINOTT, of Sheboygan, in the county ofSheboygan and State of Visconsin, have invented a new and usefulImprovement in Wood-Bending Machines; and I do declare that thefollowing' is a true and accurate description thereof, reference beinghad to the accompanying drawing and to the letters of reference markedthereon, and being a part of this specication, in which- Figure l is aplan or top view of my invention, showing the wood in position forbending. Fig. 2 is a similar view, showing the wood bent. Fig. 3 is aplan view of the eccentrically-geared pinion and rack. Fig. 4. is a planview ofthe form 7 and the wood partly bent, showing the operation of theeccentrically-geared pinion in keeping the wood away from the form toavoid lateral compression. Fig. 5 is a view of the slot in the slidingframe for receiving and retaining the strap. Fig. 6 is an end elevationof Figs. l and 2. Fig. 7 is a plan view of the form, sliding frame, andwood, in a similar position to that shown in Fig. l, exhibiting themanner of inserting the strap when said strap is to remain upon the woodafter bending; and Figs. S and 9 are views of the form, showing thedifferent ways of tying the wood by the tie-bars.

Like letters of reference made use of in the several figures indicatelike'parts.

This invention relates to a machine for bending wood; and it consists ofa sliding frame or bed for securing and pressing forward the wood and arevolving eccentric form for retaining and The form is carried upon apinion which is engaged with and revolved by a rack upon the -slidingbed, which, in turn, may be operated by a screw. The form is pivotedeccentrically, so that the wood, after it has been partially bent, willstand away from the face of the form or the periphery thereof, so thatit may not be subjected to a lateral compression, which would tend toproduce an irregularity in the bent wood, one part being liable to bemade thinner than another. The eccentrically-pivoted form avoids thisdifficulty.

To enable those skilled in the art to make and use my invention, I willproceed to describe the same with particularity, making use, in sodoing, of the aforesaid drawing.

A is a strong frame-work or table for supporting the mechanism. B is asliding frame, fitted to move in the grooved ways b b1 and hollowedtorreceive the screw C, which is provided with bearings at c in thetable, and engages a iixed nut within the frame B. When this screw isrevolved by means of the crank or wheel D the frame B is moved forwardor backward with force. E is a horizontal pinion borne by the verticalstationary shaft F, being pivoted thereon a little to one side itscenter. This pinion meshes into a rack-bar, G, carried by the slidingframe B. To accord with the eccentric shape of the pinion this rack-baris made with the teeth or cogs set at a slight angle to the line ofmotion in the bar, as will be clearly understood by reference to Fig. 3of the drawing. The form H, made of proper shape, is secured to thispinion by means of dowels h 1L h and a central nut upon the projectingend of the vertical shaft. A gradually-diminishing liange, z', projectsover the periphery of this form at the starting side to keep the woodfrom bending up or lifting under the pressure. A slight oii'set is madein the side of the sliding frame B, and tted, at its termination, withthe abutment 7c, which is of metal, and, in the present instance, iscontinued at right angles for a short distance in the form of a plate,l, furnished with a key-hole slot, m. A chain or strap is employed tohold the wood in place; and, to prevent checking and crimping, thisstrap may be left upon the bent stick, or it may be taken off and onestrap used for all the wood bent. In the latter case the end of thestrap next'the abutment is provided with a sliding catch, which en gageswith the key-hole slot and secures the strap to the machine. But in anycase it is necessary that the bent stick or wood should have a supportor strap of some kind to prevent warping in drying, and an auxiliarylight strap is used inside the strap afliXed to the machine. This auX-iliary strap need only be strong enough to prevent the wood fromsplintering or warping, ordinary Russial sheet-iron being deemedsufficient. In case one strong strap is used and left upon thestick, itis made with a simple abutment, n, to catch over the end ofthe stick,and having a hook, o, at the other end to attach it to the form at thepoint p. Fig. S illustrates the manner of applying the tie-rod l" to thestick where the light auxiliary strap is used, and Fig. 9 exhibits thesame in case of the strong single strap.

The stick to be bent is placed in the machine in the position shown atFigs. l and '7, and a key or wedge, w, driven in behind it to tighten itin place. The screw is now set in motion, and the stick or wood isforced along by an end pressure from the sliding frame, and at the sainetime is bent to the proper shape by the revolving form. Owing to theform being carried upon the eccentrically-pivoted pinion, the wood, atthat side of the form which has the lesser radius, stands, by reason ofits springiness, slightly away from the form, as clearly seen at Fig. 4,and is therefore subject to no compression from Y thestrap. Wheredifferent-sizedrforms are used the same result will be produced bymaking the pinion to work upon a true center and the teeth of the rackto coincide with the line of motion, provided the form is applied to thepinion so as to be eccentric, in the manner described.

Having described my invention, what I claim, and desire to secure byLetters Patent, is-

l. The combination ofthe sliding frame B and the eccentric revolvingform H, both constructed and arranged substantially as described andshown, and operating to give shape to said wood without lateralcompression, as explained and set forth.

2. The Ycombination of the sliding frame B, screw C, rack-bar G, andeccentrically-pivoted pinion E, substantially as specified.

3. The vertical adjustable shaft F for support` ing the pinion carriedin the sliding frame, consisting of the top and bottom pieces t u andthe vertical pieces c c, arranged in a wood-bending machine, asspecified and shown.

LEVI E. MINOTT.

Witnesses J. W. MUNDAY, J ULIUs WELCKE.

